Biology Words

a hypothesis that living things arose from nonliving matter

the energy that an atomic system must acquire before a process (such as an emission or reaction) can occur

transport of a substance (as a protein or drug) across a cell membrane against the concentration gradient; requires an expenditure of energy

the alternation of two or more different forms in the life cycle of a plant or animal

the synthesis in living organisms of more complex substances (e.g., living tissue) from simpler ones together with the storage of energy

the part of the skeleton that includes the pectoral girdle and the pelvic girdle and the upper and lower limbs

reproduction without the fusion of gametes

the part of the skeleton that includes the skull and spinal column and sternum and ribs

the property of being symmetrical about a vertical plane

production of a chemical compound by a living organism

the fatty network of connective tissue that fills the cavities of bones

breakdown in living organisms of more complex substances into simpler ones together with release of energy

a rigid layer of polysaccharides enclosing a plant membrane

a polysaccharide that is the chief constituent of all plant tissues and fibers

a specialized condensed region of each chromosome that appears during mitosis where the chromatids are held together to form an X shape

process determined by substances' composition and structure

component of arthropods' exoskeletons and bodies of fungi

the readily stainable substance of a cell nucleus consisting of DNA and RNA and various proteins; during mitotic division it condenses into chromosomes

the organs and tissues involved in circulating blood and lymph through the body

a specific sequence of three adjacent nucleotides on a strand of DNA or RNA that specifies the genetic code information for synthesizing a particular amino acid

in insects and some crustaceans: composed of many light-sensitive elements each forming a portion of an image

the state of being joined together

embryonic leaf in seed-bearing plants

the branch of biology that studies the structure and function of cells

pathological breakdown of cells by the destruction of their outer membrane

a microscopic network of actin filaments and microtubules in the cytoplasm of many living cells that gives the cell shape and coherence

a plant having foliage that is shed annually at the end of the growing season

hybridization using two traits with two alleles each

an allele that produces the same phenotype whether its paired allele is identical or different

of animals except birds and mammals

the inner portion of the gelatinous liquid inside a cell

the internal skeleton; bony and cartilaginous structure

a small asexual spore that develops inside the cell of some bacteria and algae

membranous tissue covering internal organs and other internal surfaces of the body

the exterior protective or supporting structure or shell of many animals (especially invertebrates) including bony or horny parts such as nails or scales or hoofs

an eyelike marking

the pedal extremity of vertebrates other than human beings

the ripened reproductive body of a seed plant

the physically discrete element that Darwin proposed as responsible for heredity

a gland in which gametes (sex cells) are produced

a root-like attachment in parasitic plants that penetrates and obtains food from the host

of animal or plant

restraint that attaches to something or holds something in place

a chemical bond consisting of a hydrogen atom between two electronegative atoms (e.g., oxygen or nitrogen) with one side be a covalent bond and the other being an ionic bond

a chemical reaction in which water reacts with a compound to produce other compounds; involves the splitting of a bond and the addition of the hydrogen cation and the hydroxide anion from the water

lacking affinity for water

any of the threadlike filaments forming the mycelium of a fungus

a solution having the same osmotic pressure as blood

the appearance of the chromosomal makeup of a somatic cell in an individual or species (including the number and arrangement and size and structure of the chromosomes)

evolution on a large scale extending over geologic era and resulting in the formation of new taxonomic groups

lower or hindmost part of the brain

one of two forms that coelenterates take: it is the free-swimming sexual phase in the life cycle of a coelenterate; in this phase it has a gelatinous umbrella-shaped body and tentacles

mesodermal tissue that forms connective tissue and blood and smooth muscles

the template for protein synthesis

evolution resulting from small specific genetic changes that can lead to a new subspecies

hybridization using a single trait with two alleles

cell from which another cell of an organism develops

the vegetative part of a fungus consisting of a mass of branching threadlike hyphae

the sensory and control apparatus consisting of a network of nerve cells

any toxin that affects neural tissues

a flexible rodlike structure that forms the supporting axis of the body in the lowest chordates and lowest vertebrates and in embryos of higher vertebrates

transport of a substance across a cell membrane by diffusion

thin protective membrane in some protozoa

the primary linkage of all protein structures

process in which phagocytes engulf and digest microorganisms and cellular debris; an important defense against infection

any of various compounds composed of fatty acids and phosphoric acid and a nitrogenous base; an important constituent of membranes

a change from one state (solid or liquid or gas) to another without a change in chemical composition

photosynthetic or plant constituent of plankton

the vascular structure in the uterus of most mammals providing oxygen and nutrients for and transferring wastes from the developing fetus

a thin membrane enclosing the cytoplasm of a cell

a small cellular inclusion consisting of a ring of DNA that is not in a chromosome but is capable of autonomous replication

transfer of the fine spores that contain male gametes

a small vascular growth on the surface of a mucous membrane

the property of symmetry about an axis

an allele that produces its characteristic phenotype only when its paired allele is identical

an organism that feeds on dead organic matter especially a fungus or bacterium

a membrane (as a cell membrane) that allows some molecules to pass through but not others

reproduction involving the union or fusion of a male and a female gamete

an eye having a single lens

a small usually single-celled asexual reproductive body produced by many nonflowering plants and fungi and some bacteria and protozoans and that are capable of developing into a new individual without sexual fusion

a spore-bearing branch or organ: the part of the thallus of a sporophyte that develops spores; in ferns and mosses and liverworts is practically equivalent to the sporophyte

a horizontal branch from the base of plant that produces new plants from buds at its tips

a plant body without true stems or roots or leaves or vascular system; characteristic of the thallophytes

the process whereby a transducer accepts energy in one form and gives back related energy in a different form

the transport of dissolved material within a plant

used of mollusks, especially gastropods, as snails etc.

animal constituent of plankton

a plant spore formed by two similar sexual cells